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--- linux:ubuntu [2023/11/02 08:17] – [Ubuntu basic commands] skipidar
+++ linux:ubuntu [2024/05/15 05:10] (current) – [Performance Monitoring commands] skipidar
@@ Line 22: / Line 22: @@
 ==== Essencial Commands ====
 The essencial linux commands are listed under: [[http://docstore.mik.ua/orelly/linux/run/ch04_01.htm]]
+<sxh shell>
+ls # list contents of a directory.  ls -a show hidden files.
+sudo # "super-user do" (grants administrator rights)
+sudo -i -u <username>  # login as another user e.g. root
+cd # change directory
+chmod # change file access permissions
+chown # change file and group ownership
+cp # copy
+mv # move
+rm # remove
+cat # concatenate files (dump to screen)
+emacs # text editor
+fdisk # partition table manipulator
+free -h # show free storage
+df -h # disk free (remaining / used disk space, disk size in percent, human readable)
+ncdu  # disk space visualizer
+sudo du -h ./* | sort -h  # folders and files size in current dir. Sorted.
+users # users currently logged in
+useradd # add a user
+usermod # modify existing user
+userdel # delete user
+uname # show system data (try uname -a)
+cat /etc/*-release   # shows the release name and other infos about the installed distribution
+cat /proc/version # shows distribution version, name etc.
+cat /proc/version # shows mode distribution data
+top # show current running processes
+kill # kill process by PID
+touch # create new, empty, file
+passwd # change user password
+ping -c [COUNT] # ping a network device or location (ping -c 1 google.com)
+more # show output one screen at a time
+locate # indexed search ("sudo updatedb" updates indexed database)
+find # search in the current directory and subdirectories
+ln -s myFile.txt myLink.txt   # symbolic link
+unzip /path/to/file.zip -d /targetdir # unzip
+nohup # executes a command from shell, so that it keeps on running after shell exits.
+& # When placed at the end of a command, execute that command in the background. "vim &"
+fg # bring theprocess back to the foreground. jobs; fg %1
+# enable the NTP server for time syncronization
+sudo timedatectl set-ntp on
+timedatectl
+# clear /var/log/journal/ files, leave only data of last 10d
+sudo journalctl --vacuum-time=10d
+# show 10 largest folders, sorted by size, in human friendly size scala
+du -sh * | sort -hr | head -n10
+.2G    var
+.0G    usr
+M    snap
+M    opt
+M    data
+M    boot
+.1M    etc
+.4M    home
+.1M    run
+K    root
+# example of finding files in 2 subfolders
+# and writing a cat command with them into the file replace.sh
+# man pages https://man7.org/linux/man-pages/man1/find.1.html
+find . \
+ -name "DocxToPdf.bat" -path "*/Certificates/*" -o \
+ -name "DocxToPdf.ps1" -path "*/Zeugnisse/*"  \
+ -exec echo "cat /mnt/Temp/DocxToPdf.bat > \"{}\"" > replace.sh \;
+# you can invert the path with "-not"
+find . \
+ -name "DocxToPdf.bat"  -not  -path "*/Certificates/*" -o \
+ -name "DocxToPdf.ps1"  -not  -path "*/Zeugnisse/*"  \
+ -exec echo "cat /mnt/Temp/DocxToPdf.bat > \"{}\"" > replace.sh \;
+</sxh>
 ==grep==
@@ Line 107: / Line 187: @@
 </VirtualHost>
 </code>
+==== Performance Monitoring commands ====
+{{https://s3.eu-central-1.amazonaws.com/alf-digital-wiki-pics/sharex/c12ezuvdZY.png}}
+how to diagnose a mysterious process that’s taking too much CPU, memory, IO, etc?
+The diagram below illustrates helpful tools in a Linux system.
+<sxh shell>
+vmstat # reports information about processes, memory, paging, block IO, traps, and CPU activity.
+iostat # reports CPU and input/output statistics of the system.
+netstat # displays statistical data related to IP, TCP, UDP, and ICMP protocols.
+lsof # lists open files of the current system.
+pidstat # monitors the utilization of system resources by all or specified processes, including CPU, memory, device IO, task switching, threads, etc.
+</sxh>
+Credit: Diagram by Brendan Gregg
@@ Line 1377: / Line 1478: @@
    dig -t NS google.com @1.1.1.1 ANY
+===== Upgrading packages =====
+==== Python3 ====
+<sxh shell>
+# install new version of python
+sudo add-apt-repository ppa:deadsnakes/ppa
+sudo apt update
+sudo apt install python3.12
+# setting the python12 as default version of python
+sudo update-alternatives --install /usr/bin/python3 python3 /usr/bin/python3.12 1
+# gives python3.12.2
+python3 --version
+</sxh>